• The OS allocates CPU time to each process, and prioritises them in the order of importance

Advantages

• on-line catalogues can be viewed
• much larger choice of products
• product reviews obtainable before purchase
• orders placed over internet any time day or night
• download software purchased straight away
• good and services usually cheaper on the internet
• programs that can search for best price/cheapest
• very fast placing an order has been placed as customer name, address
• and credit card details are stored so no need to re enter
• buy goods from anywhere in the world
• no need to go to shop/save travelling time

Disadvantages

• spam
• need a credit card to shop on-line/not everyone has a credit card
• hackers could retrieve credit card numbers and use them to buy goods
• security fears - of giving credit card number over the internet/fraud
• goods must be delivered/can not have the goods immediately
• can not touch/handle/see the goods

Optical Mark Recognition; Optical Character Recognition; Magnetic Ink Character Recognition ; Optical Bar Recognition

Giving answers as readers is also acceptable, that is, Optical Character Readers, Magnetic Ink Character Readers; Optical Mark Readers

• It prevents double-booking which could happen in paper-based booking system
• The customer gets immediate feedback on the availability of seats
• The customer can make  booking at any time of the day
• Emails provided by customers during booking can be used by companies for advertisement

1. Identify any computer output device suitable for each of the following tasks:

1. Generating receipts where carbon copies are required  (1mk)

• Impact printers e.g dot matrix

     b) an architectural drawing where precision is required         (1mk)

• Plotter

(c ) producing document output for a visually impaired person (1mk)

• Braille/speakers

1. Pesa Tele has offices in Nairobi and Kampala connected in a network . the management is convinced that someone is illegally gaining access to the data in their computers. State three ways in which the company can overcome this problem (3mks)

• Encryption
• Firewall
• Audit trail/tracking
• Use of passwords
• Limit the number of log-in attempts

1. Explain two ways in which the use of internet could make reporting of corruption easier (4mks)

• Interactive: the internet based technology enables real-time dialogue hence instantaneous reporting of cases
• Outreach: the technology allows the coverage of wide areas
• Social mobilization : it easy to create a network of people with similar concerns
• Anonymity : it is easier to report corruption without being  known
• Security: the message sent reaches destination without being intruded

1. State ways in which software errors can be prevent during program development

• Use of antivirus software
• Performing system update frequently
• Testing the software before implementation
• Proper training

1. Primary Storage (Memory):

   • Random Access Memory (RAM): This is a volatile memory used to store data and instructions that the CPU (Central Processing Unit) can access quickly. RAM is essential for running applications and the operating system. However, its contents are lost when the computer is powered off.
   • Read-Only Memory (ROM): ROM is a non-volatile memory that stores essential firmware and instructions necessary for the computer's boot-up process. It retains its contents even when the power is turned off.
   • Cache Memory: Cache is a small and fast memory located closer to the CPU. It stores frequently accessed data to speed up the processing.

2. Secondary Storage (Mass Storage):

   • Hard Disk Drive (HDD): HDDs use magnetic storage to store data on rotating platters. They provide relatively large storage capacities and are commonly used in computers and laptops for long-term data storage.
   • Solid-State Drive (SSD): SSDs use NAND flash memory to store data, offering faster read and write speeds than HDDs. They are more durable and consume less power, making them increasingly popular in modern computers.
   • Optical Discs: CDs, DVDs, and Blu-ray discs are examples of optical storage media. They are mainly used for distribution of software, music, movies, and archival purposes.
   • USB Flash Drives: Also known as thumb drives or pen drives, these portable storage devices use flash memory to store data and can be easily connected to a computer's USB port.
   • Memory Cards: Memory cards, such as SD cards and microSD cards, are used in various devices like cameras, smartphones, and tablets to store data, photos, videos, etc.
   • External Hard Drives: These are HDDs or SSDs contained within an external enclosure, allowing users to expand their computer's storage capacity or create backups.

highest = -1
for student = 1 to 3000
total = 0
for exam = 1 to 8
input mark
total = total + mark
if mark > highest then highest = mark
next
average = total/8
output average
next
output highest

Python code:

highest = -1
for student in range(1, 3001):
    total = 0
    for exam in range(1, 9):
        mark = int(input("Enter mark: "))
        total += mark
        if mark > highest:
            highest = mark
    average = total / 8
    print("Average:", average)
print("Highest mark:", highest)

VBA Code

Option Explicit

Sub CalculateAverageAndHighest()
    Dim highest As Integer
    Dim total As Integer
    Dim mark As Integer
    Dim average As Double
    
    highest = -1
    
    For student = 1 To 3000
        total = 0
        For exam = 1 To 8
            mark = InputBox("Enter mark:")
            total = total + mark
            If mark > highest Then
                highest = mark
            End If
        Next exam
        average = total / 8
        MsgBox "Average: " & average
    Next student
    
    MsgBox "Highest mark: " & highest
End Sub

1. Speeds up coding since converting a pseudocode into a programming language is usually faster and easier
2. Acts as documentation
3. Simplifies debugging since logical errors can be identified and corrected early in design stage
4. Language independent since it is not tied to any specific language so can be translated into different languages
5. It uses simple english-like statements

• once instructions are given, the processing runs automatically hence requiring little supervision
• tasks are processed as a group hence reducing the cost
• It is faster since the since runs automatically
• there is increased output since the processor works without any interruption

• camera
• microwave
• washing machine
• video recorder
• fridge
• sewing machine
• air conditioning
• games console
• electronic game electronic toys
• rice cooker
• dish washer
• TV
• alarm clock
• radio

• High-level languages have built-in functions;
• High-level languages have built-in libraries;
•  High-level languages have more support/help;
• High-level languages have structures (such as selection and iteration);
• High-level languages can be less machine-dependent/more portable;
• It (usually) requires fewer lines of code to be written;
• It is (usually) quicker to develop code in high-level languages;
• It is easier to find mistakes in code;
• The code is easier to maintain//understand;
• • It is easier to structure code in high-level languages;

A computer system refers to computer components that collectively function as a single unit to achieve the desired goal. It can also be defined as a collection of hardware, software, and liveware that work together to receive, process, and manage data

• It requires that a foreign key must have a matching primary key or it must be null

RFID stands for radio frequency identification. There is an RFID reader and tag.RFID is used in contactless credit and debit cards as well as in some hotel room cards. Inside an RFID tag is a chip that contains a small amount of memory. The chip is attached to a coil of wire which acts as an antenna. When an RFID tag is scanned, the reader emits radio waves which are picked up by the tag’s antenna. The power induced in the tag’s antenna from these waves is enough to power the chip which then uses its antenna to emit its own radio wave, which contains the information held on the chip. This wave is picked up by the reader which decodes the information and returns the information to a computer.

Modulation refers to the process of converting a digital signal to analog signal at the transmission end while demodulation is to converting analog signal to digital signal at the receiving end

• it is a format style that shows the listed items of different levels rather than at one level. Each level has a different indentation and numbering style

1. Chapter 1

     1.1. Introduction

                 1.1.1.Definition of terms

• Implementation

• Object code refers to a program in machine language while source code to a program in a high level language that must be translated to object code for it to be machine readable

TV remote, wireless mouse , wireless keyboard, used by robots to gauge distance and avoid obstacles,

Serial

• -more accurate/fewer errors over a longer distance
• -less expensive wiring  
• less chance of data being skewed/out of synchronization/order